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Abstract
Cd(1-x)MnxSe bulk ingot materials with 0.05 . x . 0.9 were
prepared by direct fusion of stoichiometric proportions of the
constituent high purity elements in vacuum sealed-silica tubes,
following controlled heating and cooling stages. X-ray powder
diffraction patterns indicates that for different values of x the
materials corresponding to hexagonal phase is presented.
Nearly stoichiometric films with different x values were
prepared by conventional thermal evaporation technique using
molybdenium boats in 10-3 Pa with a deposition rate 1.8 nm/sec
on optically flat glass subbstrates at 300 K. X-ray, transmission
electron microscopy, electron diffraction, scanning electron
microscopy and energy dispersive X-ray spectrometer were
emplying to characterize the deposited films. The effect of
annealing temperature in vacuum on the microstructure of the
deposited films were investigated.
The optical properties of the deposited Cd(1-x)MnxSe thin films
were calculated in the wavelength range 500-2500 nm. The
refractive index of the deposited films was found to follow the
two-term Cauchy dispersion relation. The dispersion of the
refractive index data could be described according to the simgle
osallator model, from which the oscillator parameters as well as
other optical parameters were calculated. The electric free
carrier susceptibility and the values of the carrier concentration
to the effective mass ratio were calculated. Graphical
representation of the surface and volume energy losses function
were also presented. The absorption coefficient of Cd(1-x)MnxSe
thin films with different values of x was analysed and the
optical band gap was calculated.
The DC and AC electical conductivity of the deposited films
were studied. The DC electrical conductivity revealed that, two
conduction mechanisms were observed in the temperature range
300-470 K. The activation energy for the two conduction were
calculated. The AC electrical conductivity shows a normal
behaviour according to the relation .ac=A.µ . The exponent µ
was calculated for different values of x and was found to be
temperature and composition dependent. The spectral behaviour
of both dielectric constant and the loss tangent tan . at different
ferequency and temperature were investigated.
The magnetic properties of Cd(1-x)MnxSe fine powder was also
studied in the temperature range 65 - 300 K. The coercive force,
anisotropy, reminant conduction and saturation induction were
analysed as a function of the values of x.
Keywords
Cadmium selenide – manganese selenide (CdSe–MnSe) thin
films; Thermal evaporation techniques; X-Ray Diffraction
(XRD); Scanning Electron Microscopy (SEM); Transmission
Electron Microscopy (TEM); Differential Thermal analysis
(DTA); Optical properties; Electrical Properties; Magnetic
properties